This invention relates to fluid dispensers, and in particular to a new and improved push-up type dispenser.
Push-up dispensers are widely used for dispensing a variety of materials, both powders and liquids, typically lotions and soaps. Push-up type dispensers are very desirable, permitting operation by engaging a plunger with the palm of the hand and retention of the dispensed material in the same hand.
The push-up dispensers presently known are gravity or free flow devices, with upward motion of a plunger opening a flow path from the interior of the material container, downward around the plunger to the exterior of the dispenser. Dispensers of this type have problems with leaking or dripping of material and with irregular flow of material. One solution for reducing leaking is to use a spring providing a stronger closing force, however this is an undesirable solution as it also increases the force required for actuating the dispenser.
Accordingly it is an object of the present invention to provide a new and improved push-up fluid dispenser which overcomes the leaking and dripping problem. A further object is to provide such a fluid dispenser which incorporates a positive displacement pump that can dispense a metered amount of fluid. A particular object is to provide such a dispenser incorporating a head holding capsule or one-way valve at or near the top of the dispenser valve chamber for achieving the non-drip operation.
It is another object of the invention to provide a push-up fluid dispenser which has a relatively low operating force while at the same time having a relatively high compression ratio. An additional object is to provide such a dispenser which can generate a suction for drawing liquid into the valve chamber during the return stroke.
It is another object of the invention to provide a push-up fluid dispenser with a manually operated plunger which plunger has an outlet fluid flow path therethrough with an outlet opening positioned above the lower end of the plunger, so that the dispenser fluid outlet remains a constant distance above the operators hand during the upward or dispensing stroke. A further object is to utilize this construction with a positive displacement pump so that the fluid is ejected through the outlet opening into the operators hand away from the plunger end.
These and other objects, advantages, features and results will more fully appear in the course of the following description